1. Technical Field
The present invention relates to a liquid electing head configured to eject liquid and a liquid ejecting apparatus having the same and, specifically, an ink jet printhead configured to eject ink as the liquid and an ink jet printing apparatus.
2. Description of the Related Art
In an ink jet printhead as an representative example of a liquid ejecting head, generally, ink is supplied from an ink cartridge as a liquid storage unit in which ink is filled to a head body via ink supply needles as ink supply member detachably inserted into the ink cartridge and ink flow channels formed in a supply unit such as a cartridge case in which the ink cartridge is held, and the ink supplied to the head body is discharged from nozzles by driving a pressure generating unit such as a piezoelectric element provided in the head body.
The ink jet printhead as described above has a problem such that when air bubbles present in the ink in the ink cartridge or air bubbles mixed into the ink when mounting and demounting the ink cartridge are supplied to the head body, discharge failure such as missing dot might occur due to these air babbles. In order to solve the problem as described above, there is a printhead having filters for removing air bubbles or refuses in ink provided between the ink supply needles to be inserted into the ink cartridge and a supply unit (cartridge case) (for example, see JP-A-2000-211130).
Although the ink jet printhead as described above has already downsized in the related art, further downsizing is desired. However, in the configuration as described in JP-A-2000-211130, since a filter is provided in an area where the ink supply needle of the supply unit is fixed, the supply unit needs to have a size corresponding to the surface area of the filter, so that there arises a problem such that downsizing of the head is difficult.
For example, although downsizing the supply unit by reducing the distance between the ink supply needles is contemplated, since the area for welding the ink supply needles to the supply unit together with the filters is required, it is difficult to reduce the distance between the adjacent ink supply needles. Although downsizing of the surface area of the filters by themselves is contemplated for example, since the dynamic pressure is increased, there arises a problem that the drive pressure for driving the pressure generating unit such as the piezoelectric element must be increased. When the ink supply needles are fixed to the supply unit by heat adhesion, there is a risk of formation of a clearance between them, and hence there arises a problem such that ink might leak from this clearance. In addition, when the filters and the ink supply needles are fixed individually to the supply unit, there arises a problem such that the manufacturing cost is increased to a high cost.
Such problems are present also in a liquid ejecting head configured to eject liquid other than ink in addition to the ink jet printhead.